For example, a pressure reduction valve recited in the patent literature 1 is this type of pressure reduction valve. The pressure reduction valve of the patent literature 1 includes a valve main body and a valve piece unit. A valve chamber and a restriction passage (e.g., an orifice) communicated with the valve chamber are formed in the valve main body of the pressure reduction valve. In the pressure reduction valve, refrigerant, which serves as pressure fluid, flows from the valve chamber to the restriction passage. In the valve piece unit, when a valve piece is displaced in an axial direction of an axis, an opening degree of the restriction passage is increased or decreased. The valve piece is supported by a valve support and is urged by a compression coil spring in a valve closing direction that is a direction for closing the restriction passage. The valve support includes a valve pressing portion and a plurality of spring arms. The valve pressing portion supports the valve piece. Each of the spring arms extends in a direction that intersects with a valve opening and closing direction along a peripheral wall surface of the valve chamber.
Each spring arm includes a projecting part that projects toward a radially outer side, i.e., toward the peripheral wall surface of the valve chamber. Each spring arm resiliently contacts the peripheral wall surface of the valve chamber through the projection. Therefore, the valve support always contacts the peripheral wall surface of the valve chamber through the projections, and the projections are slid along the peripheral wall surface of the valve chamber in response to the movement of the valve piece.